What is the rear brake upgrade option for 1st gen Cummins I've read about on here. Is it brake shoes that are bigger and need to be swapped?
Thanks

 

On my 1 ton dually, I went to 3 inch wide shoes and 1-1/8 bore wheel cylinders.

 

What's easy way to find out if rear brakes are 11 or 12inch? Is there way to check by VIN number?

 

Whats the part number for those 1 1/8 wheel cylinders? Thanks

 

According to my O'Reilly's receipt the PN's are WC35325 and WC35326. I don't know which is which. They cost me $11.99 each about a year ago.

Edwin

 

Silver, part numbers are varied, depending which brand you get, or which vendor you decide to go with.
If you want to go local, go on your local O’rileys or Napa website.
Punch in your model year truck. When it asks for 250 or 350, click on the 1 ton. Your local parts house on line will show 1”, 1 1/8”, or maybe even 1 3/16” choices for wheel cylinders. There you go. You can do the same with the shoes. Ours are 12”, and the upgrade for the 3/4tons are to jump to the 3” wide shoes. You will either need to buy new drums, or have them lathed out if your going to jump to the 3” shoes.

You can do the same with rockauto and all those online order places.

 

I looked up on Oreillys website and 3 inch drums are bigger, looks like rear wheels would stick out even more? https://www.oreillyauto.com/shop/bra...q=brake%20drum

 

I turned my W250 drums as deep as possible without compromising the integrity of the drum and used 3 inch shoes and 1 1/8 cylinders, then I done the DRW conversion and did it all over again...

 

Drum is the same as stated many time between 3/4and 1 ton Cummins trucks.

If it looks different, you've got one of the lookup wrong.

 

Silver, I just assisted someone on this. If you look back on O’rileys site, first look at the ones for the W250, then look at the W350, and there will be a drum that is like for like between the two model years. It will have I believe a 6” pop out for the hub part of it. Make sure you are looking at the ones for the heavy 6,500 lb axle that we have in the rears. Again, this is for comparing single axle 3/4 and 1 ton trucks(non duelly).

Oh, and the drum diameter is 14”

 

If you have a NAPA and want to go raybestos brand, I have the part numbers for:

Drums- #440-1417 14” drums
12” x 3” wide shoes #314PG

Might as well give you these, as you’ll need them

Axle seals(in hub) National #417158
Axle Flange, 8 hole gaskets- #FEL12579

 

The Dana 70 drums are ~6.3" tall/deep. (DRW or SRW is the same.) The Dana 60 drums are ~4" tall/deep. Both take 12x3" shoes.

The other 12" drum is probably for the 8lug 9.25", and the 11" is 5-lug.